______________________________________________________________________________ CU COMPARGAL is a module which plots two or more galaxy surface brightness or color distributions. Typical uses are for comparing an observed distribution with a seeing convolved fitting function such as the de Vaucouleurs formula. ______________________________________________________________________________ Enter an option: 25-NOV-1991 15:01:47.81 OPTION=CG COMPARGAL, Version 3 Enter a command: DD = Plots the normalized difference of integrated surface brightness (ADU) between two data files against radius (default) DF = Plots the normalized difference of integrated surface brightness between two formulas RD = Plots the normalized ratio of surface brightness (ADU) between two data files RF = Plots the normalized ratio of surface brightness between two formulas CD = Plots the difference of surface brightness of two data files (magnitude). Error bars and the predicted color from the Modified Hubble and de Vaucouleurs formulas, which must exist as files (magnitude), are added. SD = Plots the simple difference of surface brightness of two data files (magnitude or ADU) TD = Plots the surface brightnesses (magnitude) of two files simultaneously; error bars may be added to the first. OD = Plots the surface brightness (magnitude) of one file; error bars may be added. COMMAND=CD ....We are going to plot the color distribution and the predictions of seeing convolved fitting formulas Open the first data file Enter the file name: (default = last entry) FILE_21=M022152 ....This file, for the blue data, is of type 1 and is in units of magnitudes and arc seconds. Enter the ID of the first object: (default = last entry) ID=70 File M022152 does not begin at the center of the object Open the second data file Enter the file name: (default = last entry) FILE_22=M022151 ....This is the red data Enter the ID of the second object: (default = last entry for first object) ID_2= 70 ....We took the default File M022151 does not begin at the center of the object Enter the starting and ending radii for the plot: (default = the common range of the data files) RADII= -0.538000 1.94200 ....We took the default. This may be too much if the data begins to look noisy at large radii Enter the readout noise in electrons and the gain in electrons per ADU: (defaults = 63.9 21.3) NOISE_PARAMETERS= 63.9000 21.3000 Enter the original sky levels for the two files: SKIES=491.416 318.486 ....Units of ADU Enter the sigmas of the skies of the two files: SIGMA_SKY=0.051 0.031 ....Units of ADU Enter the magnitude calibration constants for the two files: CALIBRATIONS=27.4212 25.3366 ....The numbers added to -2.5*log(ADU) Enter the plate scale in "/pixel: (default = 0.6298) SCALE= 0.629800 ....The McGraw-Hill 1.3 m Enter the smoothing factors: (defaults = 0.3 0.3) SMOOTHING_FACTORS= 0.300000 0.300000 ....These are the factors that were used in option ED Enter the log(r)'s at which error bars are to be placed: (default = none log(r)'s=-0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Open the first artificial data file for the modified Hubble formula Enter the file name: (default = last entry) FILE_23=M022152FM ....An artificial data file constructed with option FG, the galaxy parameters, and the point spread function. It was then edited with option ED to put it in units of magntiudes and arc seconds. Open the second artificial data file for the modified Hubble formula Enter the file name: (default = last entry) FILE_24=M022151FM ....Same, but for the red. File M022152FM does not begin at the center of the object File M022151FM does not begin at the center of the object For the actual data and the formula: Mean error = 0.12251 ....The program compared the data and the formula Open the first artificial data file for the de Vaucouleurs formula Enter the file name: (default = last entry) FILE_25=M022152FV ....Blue Open the second artificial data file for the de Vaucouleurs formula Enter the file name: (default = last entry) FILE_26=M022151FV ....Red File M022152FV does not begin at the center of the object File M022151FV does not begin at the center of the object For the actual data and the formula: Mean error = 0.12952 Enter the title: (default = ID) TITLE=Galaxy 70 Enter the plot devices: G = Graphics terminal (VT100/Retrographics and Visual 550, default) G1 = Graphics terminal (GraphOn) G2 = Graphics terminal (Codonics) G3 = Graphics terminal (Micro-term) F = File T = Tektronix 4662 flat bed plotter (1200 baud) DEVICES=G ....We now inspect the plot. It is too noisy at large radii. It is easy to repeat everything with new radii. Watch. Enter an option: 25-NOV-1991 15:10:28.03 OPTION=.CG(RADII=-0.538 1.5) COMPARGAL, Version 3 ....All the prompts are automatically answered and the plot will appear with a smaller range. ______________________________________________________________________________